Approximate Bayesian Computation for astronomical model analysis : a case study in galaxy demographics and morphological transformation at high redshift

Approximate Bayesian Computation’ (ABC) represents a powerful methodology for the analysis of complex stochastic systems for which the likelihood of the observed data under an arbitrary set of input parameters may be entirely intractable – the latter condition rendering useless the standard machinery of tractable likelihood-based, Bayesian statistical inference [e.g. conventional Markov chain Monte Carlo (MCMC) simulation]. In this paper, we demonstrate the potential of ABC for astronomical model analysis by application to a case study in the morphological transformation of high-redshift galaxies. To this end, we develop, first, a stochastic model for the competing processes of merging and secular evolution in the early Universe, and secondly, through an ABC-based comparison against the observed demographics of massive (Mgal > 1011 M⊙) galaxies (at 1.5 < z < 3) in the Cosmic Assembly Near-IR Deep Extragalatic Legacy Survey (CANDELS)/Extended Groth Strip (EGS) data set we derive posterior probability densities for the key parameters of this model. The ‘Sequential Monte Carlo’ implementation of ABC exhibited herein, featuring both a self-generating target sequence and self-refining MCMC kernel, is amongst the most efficient of contemporary approaches to this important statistical algorithm. We highlight as well through our chosen case study the value of careful summary statistic selection, and demonstrate two modern strategies for assessment and optimization in this regard. Ultimately, our ABC analysis of the high-redshift morphological mix returns tight constraints on the evolving merger rate in the early Universe and favours major merging (with disc survival or rapid reformation) over secular evolution as the mechanism most responsible for building up the first generation of bulges in early-type discs.

Investigation of RuO2/Ta2O5 thin film evolution by thermogravimetry combined with mass spectrometry

The thermal evolution process of RuO2–Ta2O5/Ti coatings with varying noble metal content has been investigated under in situ conditions by thermogravimetry combined with mass spectrometry. The gel-like films prepared from alcoholic solutions of the precursor salts (RuCl3·3H2O, TaCl5) onto titanium metal support were heated in an atmosphere containing 20% O2 and 80% Ar up to 600 °C. The evolution of the mixed oxide coatings was followed by the mass spectrometric ion intensity curves. The cracking of retained solvent and the combustion of organic surface species formed were also followed by the mass spectrometric curves. The formation of carbonyl- and carboxylate-type surface species connected to the noble metal was identified by Fourier transform infrared emission spectroscopy. These secondary processes–catalyzed by the noble metal–may play an important role in the development of surface morphology and electrochemical properties. The evolution of the two oxide phases does not take place independently, and the effect of the noble metal as a combustion catalyst was proved.

ASERA : an uncontroversial evolution

The Australasian Science Education Research Association Ltd. (ASERA) is the oldest educational research association in Australasia. Starting as an informal meeting of science educators at Monash University in May 1970, it has evolved progressively without major controversy into a formally constituted limited company that promotes science education at all levels and contexts. There are no revelations of fractures within the association, and no accounts of major controversy, other than reference to a few grumbles here and there when changes were proposed. So, has the ASERA experience been positive and uplifting for all? Are there unspoken controversies? Can the uncontroversial be made controversial?

Multi-level order, friction and contradiction : the evolution of Australian film industry policy

Cultural policy studies have previously highlighted the importance of multiple logics, friction and contradiction in cultural policy. Recent developments in institutional theory provide a framework for analysing change in cultural policy which explores movement between these multiple and sometimes contradictory logics. This paper analyses the role of friction in the evolution of Australian film industry policy and in particular the tension between competing logics regarding nationalism, commercialism and the state. The paper is suggestive of the relevance of institutional theory as a framework for understanding cultural policy evolution.

Defining an Identity : The Evolution of Science Education

Research in science education is now an international activity. This book asks for the first time, Does this research activity have an identity?-It uses the significant studies of more than 75 researchers in 15 countries to see to what extent they provide evidence for an identity as a distinctive field of research.-It considers trends in the research over time, and looks particularly at what progression in the research entails.-It provides insight into how researchers influence each other and how involvement in research affects the being of the researcher as a person.-It addresses the relation between research and practice in a manner that sees teaching and learning in the science classroom as interdependent with national policies and curriculum traditions about science. It gives graduate students and other early researchers an unusual overview of their research area as a whole. Established researchers will be interested in, and challenged by, the identity the author ascribes to the research and by the plea he makes for the science content itself to be seen as problematic.

The evolution of a community of practice at the Queensland University of Technology for lecturers involved in large first year units

Communities of practice (CoPs) may be defined as groups of people who are mutually bound by what they do together (Wenger, 1998, p. 2), that is, they “form to share what they know, to learn from one another regarding some aspects of their work and to provide a social context for that work” (Nickols, 2000, para. 1). They are “emergent” in that the shape and membership emerges in the process of activity (Lees, 2005, p. 7). People in CoPs share their knowledge and experiences freely with the purpose of finding inventive ways to approach new problems (Wenger & Snyder, 2000, p. 2). They can be seen as “shared histories of learning” (Wenger, 1998, p. 86). For some time, QUT staff have been involved in a number of initiatives aimed at sharing ideas and resources for teaching first year students such as the Coordinators of Large First Year Units Working Party. To harness these initiatives and maximise their influence, the leaders of the Transitions In Project (TIP)1 decided to form a CoP around the design, assessment and management of large first year units.

Generalising unitary time evolution

In this third Quantum Interaction (QI) meeting it is time to examine our failures. One of the weakest elements of QI as a field, arises in its continuing lack of models displaying proper evolutionary dynamics. This paper presents an overview of the modern generalised approach to the derivation of time evolution equations in physics, showing how the notion of symmetry is essential to the extraction of operators in quantum theory. The form that symmetry might take in non-physical models is explored, with a number of viable avenues identified.

The Evolution of the creative industries : creative clusters, creative citizens and social network markets 創意產業的演化 : 創意集群 ,創意公民, 社會網絡市場 [published in Chinese]

The creative industries are important because they are clustered at the point of attraction for a billion or more young people around the world. They're the drivers of demographic, economic and political change. They start from the individual talent of the creative artist and the individual desire and aspiration of the audience. These are the raw materials for innovation, change and emergent culture, scaled up to form new industries and coordinated into global markets based on social networks.

Why creative industries matter to economic evolution

This paper proposes that the 'creative industries'(CIs) play an important yet widely unexamined function in economic evolution through their role in the innovation process. This occurs in terms of the facilitation of demand for novelty, the provision and development of social technologies for producer-consumer interactions, and the adoption and embedding of new technologies as institutions. The incorporation of CIs into the Schumpeterian model of economic evolution thus fills a notable gap in the social technologies of the origination, adoption and retention of innovation.

The evolution of tax morale in modern Spain

This paper studies the evolution of tax morale in Spain in the post-France era. In contrast to the previous tax compliance literature, the current paper investigates tax morale as the dependent variable and attempts to answer what actually shapes tax morale. Te analysis uses suevey data from two sources; the World Values Survey and the European Values Survey, allowing us to observe tax morale in Spain for the years 1981,1990, 1995 and 1999/2000. The sutudy of evolution of tax morale in Spain over nearly a 20-year span is particularly interesting because the political and fiscal system evolved very rapidly during this period.

Evolution and change in industrial clusters : an analysis of Hsinchu and Sophia Antipolis

The aim of this paper is to advance understandings of the processes of cluster-building and evolution, or transformative and adaptive change, through the conscious design and reflective activities of private and public actors. A model of transformation is developed which illustrates the importance of actors becoming exposed to new ideas and visions for industrial change by political entrepreneurs and external networks. Further, actors must be guided in their decision-making and action by the new vision, and this requires that they are persuaded of its viability through the provision of test cases and supportive resources and institutions. In order for new ideas to become guiding models, actors must be convinced of their desirability through the portrayal of models as a means of confronting competitive challenges and serving the economic interests of the city/region. Subsequent adaptive change is iterative and reflexive, involving a process of strategic learning amongst key industrial and political actors.